panorama of the city of Deniliquin

The city of Deniliquin, Austria (see image above) has been receiving more than twice of tourists each year due to new tourist attractions. For this reason, the city decision makers have planned the extension/modernization of the airport located to the outskirts of the city.

The modernization of the airport involves the construction of a series of buildings that could cause a serious visual impact to the neighborhoods near to the airport. The main building to be constructed is the air traffic control tower that needs to have an adequate view of the surrounding area of the airport. Therefore, a height between 10-30 meters has been planned.

In the next map we estimate the visual impact of the planned tower considering multiple altitudes, a value of 5 represents that the pixel is visible for the planned tower to a height of 30, 25, 20, 15, and 10 meters. The viewshed of the airport traffic control tower was computed considering a elevation raster map of 5 meters (See the raster description at the end of this document) in a radius of 10 kilometers. Due to computational limitations, the raster is displayed at a low spatial resolution.

Mouse over the pixels to obtain visual impact values. For a high-resolution image of the map above see here

The next line chart shows the viewshed area on different tower altitude. It can be observed that, the more the height of the tower the more the visual impact, doubling the visual area when going from a height of 10 to one of 30 meters.

Mouse over the points to obtain the values..

1 Report to the community council

The plans to modernize the Deniliquin airport will carry out a series of environmental and visual impacts. This report focuses on the last one, trying to assess the most efficient altitude, in terms of less impact, for the air traffic control tower.

Considering a radius of 10 kilometers we observe that when the altitude change from 10 meters to 30 meters, the viewshed of the tower increase from 30 to 55 kilometers square. One point to take into account is that the areas surrounding Deniliquin present a plain topography. Therefore, the tower could be seen at long distances, if there are no adverse atmospheric conditions, affecting outdoor tourist attractions.

As a result, this report recommends building an air traffic control tower of 10 meters. Although the construction of a higher tower could be beneficial in long term planning, a lower one will blend in better with the landscape and allow Deniliquin to continue maintaining that rustic and rural atmosphere for which it is so famous.

2 DEM description

Obtained from Geoscience Australia, 2015. Digital Elevation Model (DEM) of Australia derived from LiDAR 5 Metre Grid. Geoscience Australia, Canberra

The Digital Elevation Model (DEM) 5 Metre Grid of Australia derived from LiDAR model represents a National 5 metre (bare earth) DEM which has been derived from some 236 individual LiDAR surveys between 2001 and 2015 covering an area in excess of 245,000 square kilometres. These surveys cover Australia’s populated coastal zone; floodplain surveys within the Murray Darling Basin, and individual surveys of major and minor population centres. All available 1 metre resolution LiDAR-derived DEMs have been compiled and resampled using a neighbourhood-mean method to 5 metre resolution datasets for each survey area, and then merged into a single dataset for each State. Each state’s dataset is provided as a separate image within the image collection.

The acquisition of the individual LiDAR surveys and derivation of the 5m product has been part of a long-term collaboration between Geoscience Australia, the Cooperative Research Centre for Spatial Information (CRCSI), the Departments of Climate Change and Environment, State and Territory jurisdictions, Local Government and the Murray Darling Basin Authority under the auspices of the National Elevation Data Framework and Coastal and Urban DEM Program. The source datasets have been captured to standards that are generally consistent with the Australian ICSM LiDAR Acquisition Specifications with require a fundamental vertical accuracy of at least 0.30m (95% confidence) and horizontal accuracy of at least 0.80m (95% confidence).